The present invention relates generally to rocker arms.
US201010071643, which is incorporated by reference, discloses a valve opening arrangement including rocker arms for opening and closing valves. US2010/0071643 discloses that it can be desirable to provide a hydraulically movable piston for opening and closing a valve at a different timing than would occur using only a rocker arm and a cam. The inventor has using recognized that there is limited space available on the rocker arms, making it difficult to provide such a piston in many circumstances. It is desirable to address this problem.
According to a first aspect of the present invention, a hinged rocker arm comprises a first wing comprising a first opening for receiving a rocker shaft, and a first contacting surface, and a second wing comprising a second opening for receiving the rocker shaft, the second wing comprising a second contacting surface, wherein, when the first and second wings are mounted on the rocker shaft, the first contacting surface and the second contacting surface are adapted to contact each other and thereby transfer a force in a direction transverse to an axis of the rocker shaft.
According to another aspect of the present invention, a valve opening arrangement comprises a valve arrangement comprising a valve, the valve being movable against a force from a first valve position to a second valve position, a rocker shaft, and a hinged rocker arm comprising a first wing pivotably mounted on the rocker shaft and a first contacting surface, and a second wing pivotably mounted on the rocker shaft and comprising a second contacting surface, the first contacting surface and the second contacting surface being adapted to contact each other and thereby transfer a force in a direction transverse to an axis of the rocker shaft such that a third contacting surface on the hinged rocker arm contacts the valve arrangement and moves the valve against the force from the first valve position to the second valve position.